mvc中心网格显示空标题?

您可以覆盖 ShouldRenderHeader() 方法 HtmlTableGridRenderer 班级。

public class AlwaysRenderHeaderRenderer<T>
    : HtmlTableGridRenderer<T> where T : class
{
    protected override bool ShouldRenderHeader()
    {
        return true;
    }
}

<%= Html.Grid(Model).RenderUsing(new AlwaysRenderHeaderRenderer<TypeOfModel>()) %>

这种方法的一个副作用是,当网格为空时,将呈现空的表体而不是消息。提供给的任何文本 Empty() 被忽略。这对我来说不是问题,因为无论如何,我都在用JavaScript在客户机端操纵表,但是要受到警告。

从继承时 HtmlTableGridRenderer 您还可以覆盖 RenderEmpty 为了解决布兰特遇到的问题。

protected override void RenderEmpty()
    {
        RenderHeadStart();
        foreach(var column in VisibleColumns())
        {
            RenderHeaderCellStart(column);
            RenderHeaderText(column);
            RenderHeaderCellEnd(); 
        }
        RenderHeadEnd();
        RenderBodyStart();
        RenderText("<tr><td colspan=\"" + VisibleColumns().Count() + "\">" + GridModel.EmptyText + "</td></tr>");
        RenderBodyEnd();
    }

在自定义网格渲染器(子类 GridRenderer<T> )使用如下重写:

/// <summary>
/// Renders the <c>table</c> header.
/// </summary>
/// <returns>
/// Returns the negative of the results
/// of <see cref="GridRenderer<T>.IsDataSourceEmpty"/>.
/// </returns>
/// <remarks>
/// The return value of <see cref="GridRenderer<T>.IsDataSourceEmpty"/>
/// in this override has no effect on whether the Grid header is rendered.
/// 
/// However, this return value is used
/// by <see cref="GridRenderer<T>.Render"/>
/// to run <see cref="GridRenderer<T>.RenderItems"/>
/// or <see cref="GridRenderer<T>.RenderEmpty"/>.
/// </remarks>
protected override bool RenderHeader()
{
    RenderHeadStart();

    foreach(var column in VisibleColumns())
    {
        //Allow for custom header overrides.
        if(column.CustomHeaderRenderer != null)
        {
            column.CustomHeaderRenderer(new RenderingContext(Writer, Context, _engines));
        }
        else
        {
            RenderHeaderCellStart(column);
            RenderHeaderText(column);
            RenderHeaderCellEnd();
        }
    }

    RenderHeadEnd();

    return !base.IsDataSourceEmpty();
}

艾斯

protected override void RenderEmpty()
{
    RenderBodyStart();
    WriteNoRecordsAvailable(base.Writer, this._numberOfTableColumns);
    RenderBodyEnd();
}

注意 WriteNoRecordsAvailable() 是我的自定义方法,因此可以忽略它。

最后:

/// <summary>
/// This private member is duplicated
/// in order to override <see cref="GridRenderer<T>.RenderHeader"/>.
/// </summary>
readonly ViewEngineCollection _engines;

艾斯

/// <summary>
/// Initializes a new instance of the <see cref="CrmHtmlTableGridRenderer&lt;T&gt;"/> class.
/// </summary>
/// <param name="engines">The engines.</param>
public CrmHtmlTableGridRenderer(ViewEngineCollection engines)
    : base(engines)
{
    _engines = engines;
}

你就不能对检查进行注释,看看它是否应该呈现标题。我是丢失了什么,还是希望它始终显示标题?

如果是这样,那就把这行注释掉。

//if(! ShouldRenderHeader()) return false;

我没有看过所有的代码,但从您的代码片段来看,这似乎是可行的。

结合 David's 和 Brant's 答案:

protected override bool ShouldRenderHeader()
{
    return true;
}

// Oddly Render relies on ShouldRenderHeader to return IsDataSourceEmpty
// so RenderItems will always be called.
protected override void RenderItems()
{
    if (IsDataSourceEmpty())
        RenderEmpty();
    else
        base.RenderItems();
}

protected override void RenderEmpty()
{
    RenderBodyStart();
    RenderText("<tr><td colspan=\"" + VisibleColumns().Count() + "\">" + GridModel.EmptyText + "</td></tr>");
    RenderBodyEnd();
}